The escape velocity of a body on the earth surface is 11.2 ~km / s . If the same body is projected upward with velocity 22.4 ~km / s , the velocity of this body at infinite distance from the centre of the earth will be

Correct answer: B. 11.2 3 ~km / s aligned & V^ 2 =V^2-V e^2 & V^ = V^2-V e^2 & = (22.4)^2-(11.2)^2 & V^ =11.2 3 ~km / s aligned

NEET 2023

NEET 2023 · Physics · Gravitation

The escape velocity of a body on the earth surface is 11.2 ~km / s...

The escape velocity of a body on the earth surface is

11.2 \mathrm{~km} / \mathrm{s}

. If the same body is projected upward with velocity

22.4 \mathrm{~km} / \mathrm{s}

, the velocity of this body at infinite distance from the centre of the earth will be

B. $11.2 \sqrt{3} \mathrm{~km} / \mathrm{s}$

\begin{aligned} & V^{\prime 2}=V^2-V e^2 \\ & V^{\prime}=\sqrt{V^2-V e^2} \\ & =\sqrt{(22.4)^2-(11.2)^2} \\ & V^{\prime}=11.2 \sqrt{3} \mathrm{~km} / \mathrm{s}\end{aligned}